No, SF in itself can run on very modest hardware (at least for the CPU). I guess you problems are more:

- How much RAM would SF need for a decent use, with acceptable hash tables?
- How much flash storage would you need to store SF, its book, and a minimal Os to run it (I guess you'll be using a minimal stripped-down Linux?)

What hardware specs do you intend to have for your device, if that's not secret? Maybe it's still under discussion?